Call transmitter



Mar'ch 17, 1942. M. FRlTTs ET AL 2,276,954

CALL TRANSMITTER Filed Dec. 13, 1939 5 Sheets- Sheet 1 FIG! FIG. 2

Q INVENTORS' MFR/T73 FAVOOS :1 %(ac AIDMQA March 17, 1942- M; FRITTS ET AL CALL TRANSMITTER Filed Dec. 13, 1939 5 Sheets-Sheet 2 H .M. FR/TTS wvslgroks V005 ATTORNEY March 17, 1942. M. FRITTS ET AL CALL TRANSMITTER Filed Dec. 15, 1939 63 FIG. 6

5 Sheets-Sheet 4 INVENTORS: MFR/7T5 RAJ 00$ J77/QC%M ATTORNEY M. FRITTS El'AL CALL TRANSMITTER March 17, 1942.

Filed Dec. 13, 1939 5 Sheets-Sheet 5 ATTORNEY Patented Mar. 17, 1942 UNITED STATES PATENT orrlcs CALL TRANSMITTER Morris Fritts, Orange, and Frederick A. Voos, Newark, N. J., assignors to Bell Telephone Laboratories, Incorporated, New York, N. Y., a corporation of New York Application December 13, 1939, Serial No. 308,941

3 Claims. (Cl. 17990) This invention relates to call transmitter devices of the type used in automatic telephone systems for establishing talking connection and has particular reference to call transmitter devices of the preset type.

The object of the invention i to provide an improved device of this character.

A feature of the invention is the provision of a motor mechanism in the form of a spring tensioned by the rotation of a shaft geared to a manually operable lever member movable in two directions placed at the front of a casing housing the transmitter mechanism, means carried by the casing being provided for limiting the angular movement of the handle in each direction.

Another feature is the provision of clutching means operatively connecting the two-direction movable shaft to a gearing mechanism for operating the latter in one direction, the gearing mechanism actuating the operative element of a pulsing contact.

Another feature is the provision of sets of camming elements arranged in a circle and movable for selectively positioning a camming element of each set in operative relation to a contact actuating member for negativing predetermined operations of the pulsing contact.

Another feature is the provision of rotatable means mounted on a common shaft and movable manually for independently actuating gearing mechanisms for moving the sets of camming ele ments in selected positions, with means positioned by the movements of the manually oper- ,able means for indicating such positions.

Another feature is the provision of guiding means for the sets of camming element with mean automatically operable for yieldably holding such elements in each selected position.

Other novel features and advantages of the invention will appear from the following description and by the claims appended thereto, reference being had the accompanying drawings in which:

Fig. 1 is a top view;

Fig. 2 is a front elevational view;

Fig. 3 is a side elevational View, the casing and the base being shown with portions cut away;

Fig. 4 is a front assembly view shown with the casing removed, a number of operating parts being shown in section;

Fig. 5 is a vertical sectional side view taken on line 5-5 of Fig. 4 showing sets of camming elements in the operated position;

Fig. 6 is a side View shown with the casing re-- moved and a number of operating parts'with portions cut away, the camming elements being in their normal unoperated position;

Fig. 7 is a sectional View taken on line 'II of Fig. 6;

Fig. 8 is a vertical sectional view taken on line 8--8 of Fig. '7;

Fig. 9 is a rear view showing a number of operating parts with portions cut away to show the operative relation of the pulsing cam and camming elements more clearly;

Fig. 10 is a detailed view of one of the sets of camming elements and its actuating mechanism;

Fig. 11 is a horizontal sectional view taken on line II- II of Fig. 6;

Fig. 12' is a diagrammatical view of the sets of camming elements shown in positions for transmitting a certain call designation; and,

Fig. 13 is a diagrammatical view of the pulsing contact, electrically connected to a contact actuated according to the setting of the camming elements.

'In the call transmitter of the invention, a base I 0B shown in Figs. 1, 2, 3, 4, 5 and-6 is'provided for securing the mounting plates II and I2 as by a number of screws SCW. These plates are held in parallel relation to each other at their lower disposed ends by a pair of spacer members I3-I4 and at their top disposed ends by spacer members I5--I B secured to lug I1 and I8 formed'with the mounting plates I I and I2, respectively, these plates having upright extending lug portions for securing, as by screws SCW, a casing NC provided for housing the transmitter mechanism which will be hereinafter described in detail.

To the front disposed side of mounting plate II is secured, as by screws I9, a bracket 20 serving in cooperation with plate II for journaling a shaft II and on this shaft is keyed a handle lever 22 and a gear 23. This gear engages a pinion 24 keyed on one end of a shaft 25 journaled on mounting plate II and I2, one end of this -shaft being provided with a slot 26 serving for hooking one end of a helical spring 2! having its other end secured to the plate I2, as by a screw 28 shown in Fig. 9.

On shaft 25 is mounted for free'rotation thereon as a unit a gear 29 and a ratchet wheel 30, the latter being engaged by a spring-pressed pawl 3I mounted on a disc '32, keyed on shaft 25.

According to this construction, the rotation of shaft 2 I, as effected by a handle lever '22, is effective to rotate a shaft 25 through the engagement of gear 23 with pinion 24 for tensioning the spring 21, the function of which is to return the shafts 25 and 2| and the handle 22 to normal non-operated position while imparting rotary movement to gear 29 through the engagement of the spring-pressed pawl 3| with the ratchet wheel 30.

The gear 29 meshes with a pinion 33 best seen in Figs. 6, '1, 8 and 11 keyed on a spindle 34 for rotation as a unit with a gear 35, the spindle 34 being journaled in the mounting plate I2 and in a bracket 36 secured to this mounting plate, as by screws 31. The gear 35 meshes with a pinion 39 mounted on one end of a shaft 40 and movable as a unit with a gear 4| keyed to this shaft. Shaft 48 has one of its ends journaled in bracket 36 and its other end in a bracket 42, the latter being secured to the mounting plate I2 by screws 38.

The gear 4| meshes with a pinion 45 secured on a shaft 46 journaled in a bearing formed with plate I2, as shown in Figs. 5, 6, 8 and 11, and in a bearing formed with bracket 42. On shaft 46 is mounted for movement as a unit therewith a worm gear 41, a two-toothed ratchet wheel 48 and a two-lobe pulsing cam 49 disposed in engageable relation with the normally closed pulsing springs 50 and shown in Figs. 5, 6, 9 and 13 for opening the contact 52 upon the rotation of shaft 25 as effected by the tension of spring 21, the operation of pulsing cam 49 being under control of a speed governor CG having a shaft 53 provided with a worm portion 54 engaging the worm gear 41.

The disc 32, as shown in Figs. 5, 6, '1 and 8, is provided with pins 55 and 5511: serving for imparting movement to a pawl 51. in the manner of a toggle mechanism for engaging it with the twotoothed ratchet wheel 48 for stopping the operation of the pulsing mechanism in a manner which will be hereinafter described in detail.

On the upright mounting plates II and I2 is mounted a plurality of pairs of rods RI-RI, R2-R2, R3R3, R4R4, R5-R5, R6R6, R1--R1 and R8R8, each pair serving as guides for a set of camming members XI, X2, X3, X4, X5, X6,'X1 and X8 disposed in a semicircular row, there being ten cams as I, 2, 3, 4, 5, 6, 1, 8, 9 and Ill in each set arranged at equal spaced relation on similar sleeves 58 and 59 in turn mounted for sliding movement on their respective pair of rods RI-RI, RZ-RZ, etc. Each set of camming members is mounted between reinforcing arms as AR shown in Figs. 6 and having lugs L and LI provided for securing the gear racks YI, Y2, Y3, Y4, Y5, Y6, Y1 and Y8 thereon by similar screws 6|, there being in the present invention eight sets of camming members XI,

' X2, X3, etc., but the number of such a set may be increased or decreased depending upon the number of digits contained in the call designation it is desired to transmit or the call designation of the telephone exchange to which the call transmitter is connected.

The upright mounting plate I2 at its upper end is formed with laterally projecting lug portions 62 and 63, best seen in Figs. 4, 5 and 6, serving as supports for a shaft 64 on which digit indicating wheels KI, K2, K3, K4, K5, K6, K1 and K8 are mounted for free rotation thereon.

The digit indicating wheels Kl, K2, K3, etc., are formed with knurled discs DI, D2, D3, D4, D5, D6, D1, D8, D9 and DH! and pinions PI, P2, P3, P4, P5, P6, P1 and P8 engaging the gear racks YI, Y2, Y3, etc., for moving their associated sets of camming members for selectively positioning the camming members in. engageable relation with a contact actuating pawl-like member I0 upon the rotation of the knobs DI, D2, D3, etc., while springs SPM, shown in Fig. 5, engaging the pinions PI, P2, P3, etc., are provided for resiliently holding the indicating wheels KI, K2, K3, etc., in each adjusted position. Pawl 10, as shown in Figs. 4, 6 and 11, is pivotally mounted at the free end of an arm 1| keyed on the shaft 25, while a'spring 12 normally holds this pawl in position to engage one of the camming members I, 2, 3, etc., as the case may be, of each set which have been moved in selected position by the operation of knobs DI, D2, D3, etc. Pawl 10 is provided with a lug portion 13 disposed in operative relation with the normally closed contact springs 14 and 15 secured, as by screws 11., in a pile-up arrangement on the arm 1| at a point adjacent the shaft 25, as shown in Figs. 4, 5 and 6, while a spring 18, which is included in the pile-up, cooperates with spring 14 to perform switching operations well known in the automatic telephone art but which forms no part of the present invention.

In a typical example of operation for transmitting a telephone call designation as BET-26117, for example, the manual operation of knobs DI, D2, D3, D4, D5, D6 and D1, the gears PI, P2, P3, etc., and the indicating wheel KI, K2, K3, K4, K5, K6 and K1 carried thereby is effective to move the indicating wheels from their normal non-indicating positions to the positions wherein the digits of the call designation BE-261l'1, above mentioned, appear through windows W in the casing NC and actuate the gear racks YI Y2, Y3, etc., through their engagement with pinion PI, P2, P3, etc., for positioning the sets of cams XI, X2, X3, X4, etc., in the position shown diagrammatically in Fig. 2, that is, wherein a rotation of shaft 25 under tension of spring 21 will cause the wiper 10 carried by the arm 1| to engage the cam 2 of set XI, cam 3 of set X2, cam 2 of set X3, cam 6 of set X4, cam I of set X5, cam I of set X6 and cam 1 of set X'I for operating spring 1.4-and thereby opening the contact in a manner and for a purpose which will be hereinafter described in detail.

As above mentioned, the operation of handle lever 22 from the position against the stop STI shown in Fig. 2 to the position against the stop ST carried by casing NC is effective to impart a turning movement to shaft 25 for tensioning the spring 21, thus moving the arm 1| and the pawl 18 carried thereby from the position shown in full line in Figs. 4 and 12 to the starting position shown in dotted line, this movement of arm 1| causing the operation of pawl 10 upon its engagement with the cams 1, I, I, 6, 2, 3 and 2 of the call designation BIB-26117 above mentioned. During the counter-clockwise movement of arm 1|, however, it is to be noted that the pawl 10 is caused to pivot in a direction away from spring 14 and, therefore, ineffective to open the contact 16. The movement of shaft 25 and the disc 32 carried thereby is effective to engage the pin 55:): with the pawl 51 for disengaging it from Wheel 48. Upon the release of lever 22 by the operator, the spring 21 rotates a shaft 25 and the arm 1| in a clockwise direction under control of the governor CG for successively engaging the pawl 10 with the cams 2, 3, 2, 6, I, I and 1 of sets XI to X1, inclusive, while the rotation of gear 29 through the engagement of pawl 3| with ratchet wheel 38 is effective to rotate the pulsing cam 49 through the engagement of this gear with pinion 33, the gear 35 meshing with pinion 39 and the gear 4| meshing with pinion 45. The speed ratio between gear 29 and pinion 45 being such as to impart five turns to the two lobe pulsing cams 49 during the movement of wiper 10 on any one of the cams ID of sets XI, X2, X3, etc., while the length of cam l of any one set XI, X2, X3, etc., is equal to one-half turn of pulsing cam 49, cam 2 to one turn, cam 3 to one and one-half turns, .cam 4 to two turns, cam 5 to two and one-half turns, cam 6 to three turns, cam l to three and onehalf turns, cam 8 to four turns, cam 9 to four and one-half turns, and cam H] to five turns.

Normally the telephone line is closed at contact 52 operated by pulsing cam 49 and contact 16 operated by pawl 70. The rotation of pulsing cam 39 and the consequent opening of contact 52 are ineffective to transmit pulses to the telephone line during the motion of pawl 70 from its normal starting position shown in dotted lines in Figs. 4 and 12 to the point of its engagement with the cam 2 of set XI, while the passing of pawl on cam 2 of set XI opens the contact 16 during one turn of pulsing cam 49, which opens the pulsing contact 52 twice for transmitting two pulses, the first digit of the telephone call designation 2326117 corresponding to No. 351-26117 above mentioned, after which the pawl 10 permits the closure of contact 16 for negativing the operation of the pulsing cam 49 during the so-called interdigit or angular space between the cams 2 and 3 of sets XI and X2 and this operation is continued for each digit and interdigit spaces until the arm 22 has returned to normal position against the stop STI while the pin 55 carried by disc 32 causes the pivotal movement of pawl 51 to a point wherein this pivotal movement is continued by the tension of spring rs for reengaging the two-toothed ratchet wheel 48 and thereby locking the pulsing cam in its normal position and the transmitter is now ready for a subsequent call setting and transmitting operation.

The casing NC is provided with a cradle portion SCP for receiving the telephone handset HS actuating the so-called switchhook springs (not shown) in a manner and for a purpose well known in the telephone art.

What is claimed is:

1. In a call transmitter device, a shaft movable in opposite directions, a handle carried by said shaft, a second shaft geared to the first-mentioned shaft, a motor spring tensioned by the operation of the second-mentioned shaft in one of said directions upon the operation of said handle, a gearing mechanism, a pulsing cam geared to said mechanism, a clutching device mounted on the second-mentioned shaft effective in said direction for actuating said gearing mechanism, a contact actuated by said pulsing cam, a contact actuating member carried by the last-mentioned shaft, a plurality of sets of camming element arranged in a semi-circle, a third shaft, means mounted on said third shaft for positioning the camming elements of each of said sets in engageable relation with said contact actuating member for negativing predetermined operations of said pulsing cam, and means set by the operation of the first-mentioned means for indicating the adjusted position of said camming elements.

2. In a call transmitter device, a rotatable shaft movable in opposite directions, a handle carried by said shaft for moving the latter in one of said directions, a second shaft geared to the first-mentioned shaft, a motor spring tensioned by the operation of said second shaft in said direction for moving each shaft in the other direction, a gearing mechanism actuated by said second shaft in said other direction, a normally closed pulsing contact, a cam geared to said mechanism" for continuously actuating said contact during the operation of said second shaft in said other direction, an arm carried by said second shaft, normally closed contact springs carried by said arm, a pivoted pawl carried by said arm operatively associated with said springs, a plurality of sets of camming elements disposed concentric to the movement of said pawl but normally in position ineffective therewith, a third shaft, operating means for each of said sets mounted for rotary movement on said third shaft for positioning the camming elements of each of said sets in position effective relative to said pawl for causing the operation of said contact springs for negativing a number of operations of said pulsing contact, and means set by the rotation of said operating means for indicating the operation of said pulsing contact.

3. In a call transmitter, a plurality of manually operable members, adjustable camming elements set by the operation of said members, a shaft rotatable in two directions, a pulsing mechanism actuated by said shaft, means to render the operation of said shaft ineifective relative to said mechanism when said shaft is rotating in one of said directions, a lever member carried by said shaft, a two-way movable pawl pivoted at the free end of said lever, a contact carried by said lever disposed for operation by the movement of said pawl one Way, a motor spring and a handle for rotating said shaft in said ineffective direction for tensioning said spring and moving said pawl ineffectively relative to said contact, said spring operating said shaft in the other direction for engaging said pawl with the camming elements set by said manually operable members for operating said pawl the other way to cause the operation of said contact for negativing predetermined operations of said pulsing mechanism.

MORRIS FRITTS.

FREDERICK A. VOOS. 

